Label dates and datetimes

lbl_date() and lbl_datetime() produce nice labels for dates and datetimes. Where possible ranges are simplified, like like "13-14 Jul 2026" or "11:15-12:15 1 Dec 2025".

Usage

lbl_date(
  fmt = "%e %b %Y",
  symbol = "-",
  unit = as.difftime(1, units = "days"),
  single = "{l}",
  first = NULL,
  last = NULL
)

lbl_datetime(
  fmt = "%H:%M:%S %b %e %Y",
  symbol = "-",
  unit = NULL,
  single = "{l}",
  first = NULL,
  last = NULL
)

Arguments

fmt

String, list or function. A format for break endpoints.

symbol

String: separator to use for full ranges.

unit

Optional interval unit for non-overlapping labels. If not NULL, . endpoints are adjusted in the style of lbl_discrete().

single

Glue string: label for singleton intervals. See lbl_glue() for details. If NULL, singleton intervals will be labelled the same way as other intervals.

first

Glue string: override label for the first category. Write e.g. first = "<{r}" to create a label like "<18". See lbl_glue() for details.

last

String: override label for the last category. Write e.g. last = ">{l}" to create a label like ">65". See lbl_glue() for details.

Value

A function that creates a vector of labels.

Formatting endpoints

If fmt is not NULL then it is used to format the endpoints.

• If fmt is a string, then numeric endpoints will be formatted by sprintf(fmt, breaks); other endpoints, e.g. Date objects, will be formatted by format(breaks, fmt).

• If fmt is a list, then it will be used as arguments to format.

• If fmt is a function, it should take a vector of numbers (or other objects that can be used as breaks) and return a character vector. It may be helpful to use functions from the {scales} package, e.g. scales::label_comma().

See also

Other labelling functions: lbl_dash(), lbl_discrete(), lbl_endpoints(), lbl_glue(), lbl_intervals(), lbl_manual(), lbl_midpoints(), lbl_seq()

Examples

winter <- as.Date("2025-12-01") + 0:89
tab(winter, as.Date(c("2025-12-25", "2026-01-06")),
    labels = lbl_date())
#>             1-24 Dec 2025 25 Dec 2025 -  5 Jan 2026       6 Jan - 28 Feb 2026 
#>                        24                        12                        54 
new_year <- as.POSIXct("2025-12-31 23:00") + 0:120 * 60
round_midnight <- as.POSIXct(c("2025-12-31 23:59", "2026-01-01 00:05"))
tab(new_year, round_midnight,
    labels = lbl_datetime())
#>               23:00:00-23:59:00 Dec 31 2025 
#>                                          59 
#> 23:59:00 Dec 31 2025 - 00:05:00 Jan  1 2026 
#>                                           6 
#>               00:05:00-01:00:00 Jan  1 2026 
#>                                          56 
tab(new_year, round_midnight,
    labels = lbl_datetime(unit = as.difftime(1, units = "mins")))
#>               23:00:00-23:58:00 Dec 31 2025 
#>                                          59 
#> 23:59:00 Dec 31 2025 - 00:04:00 Jan  1 2026 
#>                                           6 
#>               00:05:00-01:00:00 Jan  1 2026 
#>                                          56